declare let window:any;
declare let document:any;

let perf = {
    init: (cb) => {
      let cycleFreq = 100; // 循环轮询的时间
      let isDOMReady = false;
      let isOnload = false;
      let performance = window.performance || window.mozPerformance || window.msPerformance || window.webkitPerformance;
  
      let Util = {
        addEventListener: function (name, callback, useCapture) {
          if (window.addEventListener) {
            return window.addEventListener(name, callback, useCapture);
          } else if (window.attachEvent) {
            return window.attachEvent('on' + name, callback);
          }
        },
  
        domready: function (callback) {
          if ( isOnload === true ) { return void 0; }
          let timer:any = null;
  
          if ( document.readyState === 'interactive' ) {
            runCheck();
          } else if (document.addEventListener) {
            document.addEventListener('DOMContentLoaded', function () {
              runCheck();
            }, false);
          } else if (document.attachEvent) {
            document.attachEvent('onreadystatechange', function () {
              runCheck();
            });
          }
  
          function runCheck() {
            if ( performance.timing.domInteractive ) {
              clearTimeout(timer);
              callback();
              isDOMReady = true;
            } else {
              timer = setTimeout(runCheck, cycleFreq);
            }
          }
        },
  
        onload: function (callback) {
          let timer:any = null;
  
          if (document.readyState === 'complete') {
            runCheck();
          } else {
            Util.addEventListener('load', function () {
              runCheck();
            }, false);
          }
  
          function runCheck() {
            if ( performance.timing.loadEventEnd ) {
              clearTimeout(timer);
              callback();
              isOnload = true;
            } else {
              timer = setTimeout(runCheck, cycleFreq);
            }
          }
        }
      };
  
      let reportPerf = function () {
        if (!performance) {
          return void 0;
        }
  
        // 过滤无效数据；
        function filterTime(a, b) {
          return (a > 0 && b > 0 && (a - b) >= 0) ? (a - b) : undefined;
        }
  
        // append data from window.performance
        let timing = performance.timing;
  
        let perfData = {
          // 网络建连
          pervPage: filterTime(timing.fetchStart, timing.navigationStart), // 上一个页面
          redirect: filterTime(timing.responseEnd, timing.redirectStart), // 页面重定向时间
          dns: filterTime(timing.domainLookupEnd, timing.domainLookupStart), // DNS查找时间
          connect: filterTime(timing.connectEnd, timing.connectStart), // TCP建连时间
          network: filterTime(timing.connectEnd, timing.navigationStart), // 网络总耗时
  
          // 网络接收
          send: filterTime(timing.responseStart, timing.requestStart), // 前端从发送到接收到后端第一个返回
          receive: filterTime(timing.responseEnd, timing.responseStart), // 接受页面时间
          request: filterTime(timing.responseEnd, timing.requestStart), // 请求页面总时间
  
          // 前端渲染
          dom: filterTime(timing.domComplete, timing.domLoading), // dom解析时间
          loadEvent: filterTime(timing.loadEventEnd, timing.loadEventStart), // loadEvent时间
          frontend: filterTime(timing.loadEventEnd, timing.domLoading), // 前端总时间
  
          // 关键阶段
          load: filterTime(timing.loadEventEnd, timing.navigationStart), // 页面完全加载总时间
          domReady: filterTime(timing.domContentLoadedEventStart, timing.navigationStart), // domready时间
          interactive: filterTime(timing.domInteractive, timing.navigationStart), // 可操作时间
          ttfb: filterTime(timing.responseStart, timing.navigationStart),  // 首字节时间  
        };
  
        return perfData;
      };
  
      Util.domready(function () {
        let perfData:any = reportPerf();
        perfData.type = 'domready';
        cb(perfData);
      });
  
      Util.onload(function () {
        let perfData:any = reportPerf();
        perfData.type = 'onload';
        cb(perfData);
      });
    }
  };
  
  export default perf;